Cache control for web application resources

ABSTRACT

Cache control for Web application resources can include receiving a cache manifest for a Web application, wherein the cache manifest specifies a Web page of the Web application, and determining, using a processor, a resource that is required by the Web page. A closure collection can be built that includes the resource required by the Web page. A reference to the resource can be written to the cache manifest.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of U.S. application Ser. No.13/537,605, filed on Jun. 29, 2012, the entirety of which isincorporated herein by reference.

BACKGROUND

A Web application generally refers to an application that is implementedas a collection of Web pages that operate in a cooperative manner over anetwork. A Web application can be built using a variety of differenttypes of resources such as Cascading Style Sheets (CSS), JavaScript®,HyperText Markup Language (HTML), image files, and the like. Theperformance of the Web application is dependent upon many factorsincluding, for example, the organization and interaction of thesevarious resources when executed.

BRIEF SUMMARY

One or more embodiments disclosed within this specification relate tocache control for Web application resources.

An embodiment can include a method. The method can include generating acache manifest for a Web application, wherein the cache manifestspecifies a Web page of the Web application, and determining, using aprocessor, a resource that is required by the Web page. The method caninclude building a closure collection including the resource required bythe Web page and writing a reference indicating the resource to thecache manifest.

Another embodiment can include a method. The method can includedeploying a first component of a Web application to a first dataprocessing system. The first component can include a content cachespecifying a list of resources and a closure collection that includeseach resource in the list of the content cache. The method also caninclude deploying a second component of the Web application to a seconddata processing system. The second component includes at least a portionof the Web application not included in the first component.

Another embodiment can include a system. The system can include aprocessor configured to initiate executable operations. The executableoperations can include generating a cache manifest for a Webapplication, wherein the cache manifest specifies a Web page of the Webapplication, determining a resource that is required by the Web page,and building a closure collection including the resource required by theWeb page. A reference indicating the resource can be written to thecache manifest.

Another embodiment can include a system. The system can include a firstdata processing system storing a first component of a Web application.The first component can include a content cache specifying a list ofresources and a closure collection including each resource in the listof the content cache. The system further can include a second dataprocessing system communicatively linked with the first data processingsystem via a network. The second data processing system can store asecond component of the Web application. The second component includesat least a portion of the Web application not included in the firstcomponent.

Another embodiment can include a computer program product. The computerprogram product can include a computer readable storage medium havingstored thereon program code that, when executed, configures a processorto perform executable operations. The operations can include generatinga cache manifest for a Web application, wherein the cache manifestspecifies a Web page of the Web application, determining a resource thatis required by the Web page, and building a closure collection includingthe resource required by the Web page. A reference indicating theresource can be written to the cache manifest.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a block diagram illustrating a system for cache control of Webapplication resources in accordance with an embodiment disclosed withinthis specification.

FIG. 2 is a block diagram illustrating operation of the system describedwith reference to FIG. 1 in accordance with another embodiment disclosedwithin this specification.

FIG. 3 is a flow chart illustrating a method of operation for cachecontrol of Web application resources in accordance with anotherembodiment disclosed within this specification.

FIG. 4 is a block diagram illustrating a communication system in which aWeb application separated into components is hosted in accordance withanother embodiment disclosed within this specification.

DETAILED DESCRIPTION

As will be appreciated by one skilled in the art, aspects of the presentinvention may be embodied as a system, method or computer programproduct. Accordingly, aspects of the present invention may take the formof an entirely hardware embodiment, an entirely software embodiment(including firmware, resident software, micro-code, etc.) or anembodiment combining software and hardware aspects that may allgenerally be referred to herein as a “circuit,” “module” or “system.”Furthermore, aspects of the present invention may take the form of acomputer program product embodied in one or more computer readablemedium(s) having computer readable program code embodied, e.g., stored,thereon.

Any combination of one or more computer readable medium(s) may beutilized. The computer readable medium may be a computer readable signalmedium or a computer readable storage medium. A computer readablestorage medium may be, for example, but not limited to, an electronic,magnetic, optical, electromagnetic, infrared, or semiconductor system,apparatus, or device, or any suitable combination of the foregoing. Morespecific examples (a non-exhaustive list) of the computer readablestorage medium would include the following: an electrical connectionhaving one or more wires, a portable computer diskette, a hard diskdrive (HDD), a solid state drive (SSD), a random access memory (RAM), aread-only memory (ROM), an erasable programmable read-only memory (EPROMor Flash memory), an optical fiber, a portable compact disc read-onlymemory (CD-ROM), a digital versatile disc (DVD), an optical storagedevice, a magnetic storage device, or any suitable combination of theforegoing. In the context of this document, a computer readable storagemedium may be any tangible medium that can contain, or store a programfor use by or in connection with an instruction execution system,apparatus, or device.

A computer readable signal medium may include a propagated data signalwith computer readable program code embodied therein, for example, inbaseband or as part of a carrier wave. Such a propagated signal may takeany of a variety of forms, including, but not limited to,electro-magnetic, optical, or any suitable combination thereof. Acomputer readable signal medium may be any computer readable medium thatis not a computer readable storage medium and that can communicate,propagate, or transport a program for use by or in connection with aninstruction execution system, apparatus, or device.

Program code embodied on a computer readable medium may be transmittedusing any appropriate medium, including but not limited to wireless,wireline, optical fiber, cable, RF, etc., or any suitable combination ofthe foregoing. Computer program code for carrying out operations foraspects of the present invention may be written in any combination ofone or more programming languages, including an object orientedprogramming language such as Java™, Smalltalk, C++ or the like andconventional procedural programming languages, such as the “C”programming language or similar programming languages. The program codemay execute entirely on the user's computer, partly on the user'scomputer, as a stand-alone software package, partly on the user'scomputer and partly on a remote computer, or entirely on the remotecomputer or server. In the latter scenario, the remote computer may beconnected to the user's computer through any type of network, includinga local area network (LAN) or a wide area network (WAN), or theconnection may be made to an external computer (for example, through theInternet using an Internet Service Provider).

Aspects of the present invention are described below with reference toflowchart illustrations and/or block diagrams of methods, apparatus(systems), and computer program products according to embodiments of theinvention. It will be understood that each block of the flowchartillustrations and/or block diagrams, and combinations of blocks in theflowchart illustrations and/or block diagrams, can be implemented bycomputer program instructions. These computer program instructions maybe provided to a processor of a general purpose computer, specialpurpose computer, or other programmable data processing apparatus toproduce a machine, such that the instructions, which execute via theprocessor of the computer, other programmable data processing apparatus,or other devices create means for implementing the functions/actsspecified in the flowchart and/or block diagram block or blocks.

These computer program instructions may also be stored in a computerreadable medium that can direct a computer, other programmable dataprocessing apparatus, or other devices to function in a particularmanner, such that the instructions stored in the computer readablemedium produce an article of manufacture including instructions whichimplement the function/act specified in the flowchart and/or blockdiagram block or blocks.

The computer program instructions may also be loaded onto a computer,other programmable data processing apparatus, or other devices to causea series of operational steps to be performed on the computer, otherprogrammable apparatus or other devices to produce a computerimplemented process such that the instructions which execute on thecomputer or other programmable apparatus provide processes forimplementing the functions/acts specified in the flowchart and/or blockdiagram block or blocks.

One or more embodiments disclosed within this specification relate tocache control for Web application resources. In accordance with theinventive arrangements disclosed within this specification, theresources that are utilized by a Web application can be evaluated todistinguish those resources that are required from those resources thatare not required. One or more of the required resources can be includedwithin a closure collection. A cache manifest for the closure collectioncan be generated and/or updated that lists the contents of the closurecollection.

The Web application can be configured, e.g., separated, into two or moredifferent components. A first component can include the closurecollection and the cache manifest. A second component can include one ormore portions, e.g., any remaining portions, of the Web application notincluded within the first component. By configuring the Web applicationas two or more components, the Web application can be deployed to anetwork that utilizes edge server technology. The servers within thenetwork can analyze the Web application and move the first component ofthe Web application to a server that is closer, in terms of distance,hops of the network, or another metric, to the user or users that willbe accessing the Web application. The remaining components can be storedelsewhere in other servers of the network until needed.

In this manner, the Web application can be served to a user in anefficient manner since portions of the Web application, e.g., the firstcomponent including those portions accessed by users with a high degreeof frequency, are already stored on a server that is close to the user.The distance of the server to the user results in faster response timesfor the user and improved performance of the Web application. Otherportions of the Web application, e.g., the second component, can bestored in one or more other servers at locations that are geographicallyfarther from the user than the server storing the first component.

As used within this specification, a “Web application” refers to anapplication that is formed using one or more Web technologies such asHyperText Markup Language, HyperText Transfer Protocol (HTTP),JavaScript®, etc. A Web application includes one or more Web pages. Inone aspect, each Web page of a Web application is an HTML file. Itshould be appreciated that while a Web application can be operated overa public network such as the Web (e.g., the Internet), a Web applicationalso can operate over a private network.

FIG. 1 is a block diagram illustrating a system 100 for cache control ofWeb application resources in accordance with an embodiment disclosedwithin this specification. As illustrated, system 100 can include atleast one processor 105 coupled to memory elements 110 through a systembus 115 or other suitable circuitry. Accordingly, system 100 can storeprogram code within memory elements 110. Processor 105 can execute theprogram code accessed from memory elements 110 via system bus 115.

In one aspect, system 100 is implemented as a data processing system,such as a computer, that is suitable for storing and/or executingprogram code. It should be appreciated, however, that system 100 can beimplemented in the form of any system including a processor and memorythat is capable of performing the functions and/or operations describedwithin this specification.

Memory elements 110 can include one or more physical memory devices suchas, for example, local memory 120 and one or more bulk storage devices125. Local memory 120 refers to RAM or other non-persistent memorydevice(s) generally used during actual execution of the program code.Bulk storage device(s) 125 can be implemented as a hard disk drive(HDD), solid state drive (SSD), or other persistent data storage device.System 100 also can include one or more cache memories (not shown) thatprovide temporary storage of at least some program code in order toreduce the number of times program code must be retrieved from bulkstorage device 125 during execution.

Input/output (I/O) devices such as a keyboard 130, a display 135, and apointing device 140 optionally can be coupled to system 100. The I/Odevices can be coupled to system 100 either directly or throughintervening I/O controllers. One or more network adapters 145 also canbe coupled to system 100 to enable system 100 to become coupled to othersystems, computer systems, remote printers, and/or remote storagedevices through intervening private or public networks. Modems, cablemodems, and Ethernet cards are examples of different types of networkadapters 145 that can be used with system 100.

As pictured in FIG. 1, memory elements 110 can store development tool150. Development tool 150, being implemented in the form of executableprogram code, can be executed by system 100 and, as such, is consideredpart of system 100. Execution of development tool 150 configures system100 to perform and/or initiate the executable operations describedwithin this specification relating to cache management of Webapplication resources.

FIG. 2 is a block diagram illustrating operation of system 100 asdescribed with reference to FIG. 1 in accordance with another embodimentdisclosed within this specification. Like numbers will be used to referto the same items throughout this specification. As shown, system 100 isexecuting development tool 150.

In one embodiment, system 100 receives a Web application 205A. Webapplication 205A includes one or more Web pages 210. In one aspect, Webapplication 205A can be provided to system 100 in the form of a WebApplication Archive (WAR) file or in another container or format. Ingeneral, system 100 processes Web application 205A and generates amodified version illustrated as Web application 205B. System 100, forexample, can introspect Web application 205A to generate Web application205B as described within this specification.

Web application 205B is functionally equivalent to Web application 205A.Whereas Web application 205A can be viewed as a single, monolithicstructure or component, Web application 205B includes a first component215 and a second component 220. The dashed lines corresponding to Webapplication 205B in FIG. 2 indicate that while components 215 and 220,taken collectively, represent Web application 205B, each of components215 and 220 is separate and distinct.

As shown, component 215 includes a cache manifest 225 and a closurecollection 230. In one embodiment, system 100 generates cache manifest225 and closure collection 230. In one exemplary implementation, cachemanifest 225 is implemented in accordance with the Offline WebApplications, W3C Working Group Note, dated May 30, 2008 (W3Cspecification). For example, cache manifest 225 can be implemented asdescribed in section 3 entitled “Offline Application Caching APIs”. Inthe W3C specification, referring to section 3, a “manifest” attributecan be used. The “manifest” attribute can take a Universal ResourceIdentifier (URI) that specifies a list of files to be included withinclosure collection 230.

The W3C specification is one example of a format that can be used and/orfollowed in implementing cache manifest 225. It should be appreciated,however, that any of a variety of formats and/or protocols can be used.Accordingly, use of the W3C specification as an exemplary implementationof cache manifest 225 is not intended as a limitation of the one or moreembodiments disclosed within this specification.

In one aspect, a developer, e.g., a human being, can manually primecache manifest 225 by adding one or more entries for Web pages 210 ofWeb application 205A. In another aspect, system 100 can automaticallydetermine one or more Web pages 210 of Web application 205 for which anentry is added to cache manifest 225. In a primed state, whether primedmanually or automatically by system 100, cache manifest 225 specifies,e.g., includes a reference to, one or more Web pages 210 of Webapplication 205A.

A reference to a Web page 210 of Web application 205A can be specifiedwithin cache manifest 225 in any of a variety of different ways. Forexample, a reference to a Web page can be specified as a pathname, afile name, a URI, or the like. Specifying a Web page 210 within cachemanifest 225 indicates that the Web page is to be included in closurecollection 230 and component 215 of Web application 205B. In the primedstate, cache manifest 225 does not specify any resources that arerequired for the Web pages specified therein. Rather, cache manifest 225specifies only a list of one or more Web pages 210 of Web application205A.

In one embodiment, the list of Web pages 210 that primes cache manifest205 is not a comprehensive list that includes each Web page 210 of Webapplication 205A. The list of Web pages 210 with which cache manifest225 is primed is a subset of the entire set of Web pages 210 forming Webapplication 205A.

Once cache manifest 225 is primed, or in a primed state, system 100undertakes an evaluation of cache manifest 225 and identifies resourcesthat are used or required by the Web page(s) 210 listed in cachemanifest 225. System 100 retrieves each resource that is identified andstores the resource within closure collection 230. System 100 furtheradds an entry into cache manifest 225 for each resource that is storedwithin closure collection 230. Cache manifest 225 ultimately specifies alist of resources that are considered required for operation theparticular ones of Web pages 210 specified within cache manifest 225 andwhich are also stored within closure collection 230.

In one embodiment, closure collection 230 is a container that includesthe various resources that have been retrieved according to primed cachemanifest 225. Examples of containers can include archive files,packages, compressed archive files, Web archives, or the like. Theparticular type of container that is used to store resources in the formof closure collection 230 is not intended as a limitation of the one ormore embodiments disclosed within this specification. Rather, any of avariety of available container and/or file types can be used.

When system 100 completes processing, Web application 205A istransformed into Web application 205B, which includes component 215 andcomponent 220. Component 215 includes closure collection 230 and cachemanifest 225. Cache manifest 225 specifies each resource that has beenstored within closure collection 230. In one aspect, cache manifest 225specifies each resource placed in closure file 230 in relation to theparticular Web page from which the resource was determined.

Accordingly, Web application 205B can be released in the form to twoseparate and distinct components 215 and 220. Each of components 215 and220 can be implemented as any of the various container types described.As such, when Web application 205B is deployed, component 215 can bedeployed to a first server while component 220 is deployed to a secondand different server. The first server can be located a distance from aclient accessing Web application 205B that is smaller than the distancebetween the client and the second server. As noted, distance can bemeasured in terms of geographic distance, network distance (e.g., hopsor the like), or using another metric.

Accordingly, those resources of Web application 205B that are includedwithin component 215 can be delivered to requesting clients moreefficiently than those included in component 220. Resources withincomponent 220 can be stored in a server at a location that is fartherfrom the client and which may be less expensive to utilize. Further, byreducing the amount of data for Web application 205B that is stored onthe first server, which may be an expensive or “in-demand” server, theserver can store additional resources and/or Web applications.

FIG. 3 is a flow chart illustrating a method 300 of operation for cachemanagement of Web application resources in accordance with anotherembodiment disclosed within this specification. Method 300 can beimplemented by a system as described with reference to FIGS. 1 and 2 ofthis specification.

In block 305, the system can receive a reference to a Web application.For example, a developer can provide the system with a reference to aWeb application or otherwise identify a Web application to the systemfor processing. In block 310, the system can determine one or more Webpages of the Web application that are to be used in priming a cachemanifest to be generated by the system.

As discussed, in one embodiment, the developer can manually specify oneor more Web pages that are to be used to prime the cache manifest. Forexample, the developer can select Web pages that he or she hasdetermined will likely be accessed by users with greater frequency thanother Web pages. In illustration, a home Web page or index Web page ofthe Web application can be selected while an administrative Web page ora help Web page of the Web application may not be selected.

In another embodiment, the system can inspect the Web application andautomatically select one or more Web pages that are used to prime thecache manifest that is to be generated. For example, the system canselect Web pages having a particular file name such as “index,” “main,”or the like. The system can maintain a list of file names or othercriteria that can be used to evaluate Web pages of the Web application.Any Web page matching the enumerated criteria can be selected. Thisallows a developer to use a particular naming convention or otherattributes during development to designate, or otherwise distinguish,those Web pages to be used to prime the cache manifest from those Webpages that are not to be selected.

In block 315, the system can generate the cache manifest and prime thecache manifest with the Web page(s) selected in block 310. In doing so,the system inserts, or adds, a reference to each of the Web page(s)selected in block 310 within the cache manifest.

In block 320, the system can determine resources that are required bythe Web pages specified within the primed cache manifest. The system candetermine resources that are required by the Web pages using any of avariety of different techniques.

In one embodiment, the system determines that any resources accessed bya Web page listed in the cache manifest that are static are requiredresources. A static resource is a file that does not change over time. Adynamic resource refers to a resource that does change over time. Anexample of a dynamic resource is data that is obtained from a Webservice or other function such as a database query or the like. The datachanges according to the parameters of the query performed, the time thequery is performed, etc. Dynamic resources specified by a Web pagelisted in the primed cache manifest are not considered requiredresources.

In one aspect, the system can determine resources by detecting resourcesindicated by target attributes, e.g., targets, within the HTML of theWeb pages with which the cache manifest is primed. Examples of staticresources that can be detected as targets can include CSSs, image files,and the like. The detection of such static resources can be performedthrough an analysis of URIs, using recursive analysis, or the like. Insome cases, when a target is identified, the system can determinewhether the target is dynamic or static according to the type of thefile which can be indicated by the extension of the file.

In the case of JavaScript® files being detected as static resources, forexample, an in-depth analysis is required. The system can be configuredto understand the syntactical and semantic references to JavaScript®resources within the application source code. For instance, in the caseof a popular Ajax (Asynchronous JavaScript and XML) toolkit called “DojoToolkit,” when the statement “dojo.require( )” is used in JavaScriptsource code, such a reference indicates that a separate “.js” file isrequired. The system can identify the “.js” file.

The examples illustrated above are provided for purposes ofillustration. The system can be configured to identify variousprogrammatic structures that may be included within, or specified by, aWeb page listed in the primed cache manifest as indicators of requiredfiles. As such, the particular examples provided are not intended aslimitations of the one or more embodiments disclosed within thisspecification.

In block 325, the system can retrieve the resources that are identifiedin block 320. The system can download or copy the resources, forexample. In block 330, the system can build the closure collection. Thesystem can include each of the resources that were retrieved in block325 within the closure collection. For example, when retrieving aresource, the resource can be stored or written to the closurecollection. Thus, the closure collection includes only required, e.g.,static, resources and excludes dynamic resources utilized by the Webpages with which the cache manifest is primed.

In block 335, the system can write a reference for each resourceincluded in the closure collection to the cache manifest. In one aspect,the references that are written within the cache manifest can beassociated with the particular Web page from which the correspondingresource was identified. For example, if Web page A is specified in theprimed cache manifest, and resource A is determined to be required forWeb page A and stored within the closure collection, the system writes areference specifying resource A within the cache manifest. The referenceto resource A written to the cache manifest is associated with Web pageA to indicate that the resource is required by Web page A.

In block 340, the system optionally can consolidate resources that arein the closure collection. Consolidation can be performed for text-basedfiles, for image files, or the like. In the case of text based files,for example, two or more different files can be consolidated into asingle file. The resulting consolidated file has the same functionalityas the two or more individual files that were consolidated or merged.

In the case of two or more image files, the image files can be mergedinto a single image file. For example, two or more images that aredisplayed concurrently by a Web page and that are proximate or adjacentto one another can be consolidated into a single image, e.g., acomposite. The resulting consolidated image file visually appears, whenrendered as part of the Web page, the same as the two or more individualimage files would have appeared prior to consolidation when displayed.

One example of a consolidation function is the “minify” function. Theminify function refers to an available function that combine multiplefiles, e.g., CSS or JavaScript files, into a single file. The minifyfunction also can remove unnecessary characters from the resulting file(e.g., whitespace and comments), and further can apply compressionencoding.

Consolidating resources within the closure collection can furtherenhance the performance of the Web application. One result ofconsolidation is that the closure collection includes a smaller numberfiles that need to be cached. Another result is that the size of theclosure collection is reduced. In one aspect, consolidation alsoincludes compressing one or more of the resources in the closurecollection, or the closure collection as a whole, to reduce the size ofthe closure collection. Consolidation also makes the cache manifesteasier to maintain as fewer entries are included as described in block345 to follow. Though not illustrated in FIG. 3, it should beappreciated that in consolidating files, any internal reference withinthe Web application to a consolidated resource also can be updated toindicate, or point to, the consolidated file that includes the resource.

In block 345, the system can update the cache manifest according to anyconsolidation that is performed in block 340. In particular, anyreferences to resources that are included in the cache manifest thathave been consolidated can be replaced with a reference to theconsolidated file. Where, for example, the cache manifest included onereference to resource A, a reference to resource B, a reference toresource C, and a reference to resource D, the four references areremoved and replaced with a single reference to the consolidatedresource (i.e., the consolidated resource into which resources A, B, C,and D were merged).

In block 350, the system can separate the Web application into two ormore components. The first component, for example, includes the closurecollection and the cache manifest. The second component includes anyportions of the Web application not included in the first component. Forexample, the second component can include any Web pages of the Webapplication not specified within the cache manifest. The secondcomponent may or may not include resources, e.g., static resources,utilized by the Web pages included therein.

In block 355, the Web application can be deployed. The Web applicationcan be deployed, e.g., stored, on one or more servers for hosting. Inone aspect, the first component is deployed to a first server, while thesecond component is deployed to a second and different server.

FIG. 4 is a block diagram illustrating a communication system 400 inwhich a Web application separated into components is hosted inaccordance with another embodiment disclosed within this specification.As shown, communication system 400 includes servers 405, 410, 415, and420, each being coupled by a network 425. A client 430 also can becoupled to any one of servers 405-420 via network 425.

Each of servers 405-420 and client 430 can be implemented as a dataprocessing system as previously described within this specification.While servers 405-420 and client 430 generally can be implemented ascomputer systems, client 430 may also be implemented as a portablecomputing system, a mobile device, or the like.

Network 425 represents any of a variety of communication networks or acombination of two or more communication networks coupled together. Forexample, network 425 can be implemented as, or include, a WAN, a LAN, awireless network, a mobile network, the Internet, or variouscombinations thereof, to which data processing systems (e.g., mobiledevices, communication devices, computers, etc.) can be coupled.

It will be appreciated that for simplicity and clarity of illustration,elements shown in the figures have not necessarily been drawn to scale.For example, the dimensions of some of the elements may be exaggeratedrelative to other elements for clarity. Referring to FIG. 4, however,server 405 is placed at a physical, or geographic, location that is theshortest distance to the location of client 430.

In one aspect, each of servers 405-420 can be configured withoperational software that allows servers 405-420 to exchange resources,e.g., Web applications or components thereof, according one or morecriteria including, for example, the location of one or more clientsaccessing the resources. In this example, client 430 is accessing Webapplication 205B. Accordingly, server 405 stores component 215 toprovide client 430 with greater response time and performance for Webapplication 205B.

Component 220 of Web application 205B can be stored at a differentserver, e.g., server 420. Server 420, for example, can be placed at alocation that is a greater distance from client 430 than server 405.Server 420 may be in a location that is less expensive to operatecompared to server 405. Server 405, for example, can be located in ahighly populated area whereas server 420 is not. Because server 405 doesnot store or host the entirety of Web application 205B, server 405 canbe used to store and/or host more resources for one or more other Webapplications than would have been the case had component 220 also beenstored and/or hosted on server 405.

The one or more embodiments disclosed within this specification providetechniques for separating a Web application into two or more components.The components can be deployed to different servers at differentlocations within a network so that those resources of the Webapplication that are most frequently accessed or otherwise deemedrequired can be located closer to the client(s) accessing the Webapplication. Resources of the Web application not deemed required orthat are accessed less frequently can be deployed to locations fartherfrom the client thereby permitting less expensive and more efficientusage of the communication system.

The flowchart and block diagrams in the Figures illustrate thearchitecture, functionality, and operation of possible implementationsof systems, methods and computer program products according to variousembodiments of the present invention. In this regard, each block in theflowchart or block diagrams may represent a module, segment, or portionof code, which comprises one or more executable instructions forimplementing the specified logical function(s). It should also be notedthat, in some alternative implementations, the functions noted in theblock may occur out of the order noted in the figures. For example, twoblocks shown in succession may, in fact, be executed substantiallyconcurrently, or the blocks may sometimes be executed in the reverseorder, depending upon the functionality involved. It will also be notedthat each block of the block diagrams and/or flowchart illustration, andcombinations of blocks in the block diagrams and/or flowchartillustration, can be implemented by special purpose hardware-basedsystems that perform the specified functions or acts, or combinations ofspecial purpose hardware and computer instructions.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention. Asused herein, the singular forms “a,” “an,” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “includes,”“including,” “comprises,” and/or “comprising,” when used in thisspecification, specify the presence of stated features, integers, steps,operations, elements, and/or components, but do not preclude thepresence or addition of one or more other features, integers, steps,operations, elements, components, and/or groups thereof.

Reference throughout this specification to “one embodiment,” “anembodiment,” or similar language means that a particular feature,structure, or characteristic described in connection with the embodimentis included in at least one embodiment disclosed within thisspecification. Thus, appearances of the phrases “in one embodiment,” “inan embodiment,” and similar language throughout this specification may,but do not necessarily, all refer to the same embodiment.

The term “plurality,” as used herein, is defined as two or more thantwo. The term “another,” as used herein, is defined as at least a secondor more. The term “coupled,” as used herein, is defined as connected,whether directly without any intervening elements or indirectly with oneor more intervening elements, unless otherwise indicated. Two elementsalso can be coupled mechanically, electrically, or communicativelylinked through a communication channel, pathway, network, or system. Theterm “and/or” as used herein refers to and encompasses any and allpossible combinations of one or more of the associated listed items. Itwill also be understood that, although the terms first, second, etc. maybe used herein to describe various elements, these elements should notbe limited by these terms, as these terms are only used to distinguishone element from another unless stated otherwise or the contextindicates otherwise.

The term “if” may be construed to mean “when” or “upon” or “in responseto determining” or “in response to detecting,” depending on the context.Similarly, the phrase “if it is determined” or “if [a stated conditionor event] is detected” may be construed to mean “upon determining” or“in response to determining” or “upon detecting [the stated condition orevent]” or “in response to detecting [the stated condition or event],”depending on the context.

The corresponding structures, materials, acts, and equivalents of allmeans or step plus function elements in the claims below are intended toinclude any structure, material, or act for performing the function incombination with other claimed elements as specifically claimed. Thedescription of the embodiments disclosed within this specification havebeen presented for purposes of illustration and description, but are notintended to be exhaustive or limited to the form disclosed. Manymodifications and variations will be apparent to those of ordinary skillin the art without departing from the scope and spirit of theembodiments of the invention. The embodiments were chosen and describedin order to best explain the principles of the invention and thepractical application, and to enable others of ordinary skill in the artto understand the inventive arrangements for various embodiments withvarious modifications as are suited to the particular use contemplated.

What is claimed is:
 1. A system comprising: a processor configured toinitiate executable operations comprising: generating a cache manifestfor a Web application, wherein the cache manifest specifies a Web pageof the Web application; determining a resource that is required by theWeb page; building a closure collection including the resource requiredby the Web page; writing a reference indicating the resource to thecache manifest; separating the Web application into a first componentcomprising the closure collection and the cache manifest and a secondcomponent, distinct from the first component, including at least aportion of the Web application not included in the first component;deploying the first component to a first server system; and deployingthe second component to a second server system different than the firstserver system.
 2. The system of claim 1, wherein determining a resourcethat is required by the Web page comprises: determining a targetspecified by the Web page as the resource.
 3. The system of claim 1,wherein the processor is further configured to initiate an executableoperation comprising: determining that the resource is a staticresource.
 4. The system of claim 1, wherein each resource includedwithin the closure collection is a static resource.
 5. The system ofclaim 1, wherein the processor is further configured to initiate anexecutable operation comprising: compressing at least a portion of theclosure collection.
 6. The system of claim 1, wherein the closurecollection comprises at least a first resource and a second resource,wherein the processor is further configured to initiate an executableoperation comprising: consolidating the first resource and the secondresource into a single, consolidated resource.
 7. A system comprising: aprocessor configured to initiate executable operations comprising:deploying a first component of a Web application to a first dataprocessing system to be stored thereon, wherein the first componentcomprises a content cache specifying a list of resources for a Web pageof the Web application and a closure collection comprising each resourcein the list of resources of the content cache; and deploying a secondcomponent of the Web application to a second data processing systemcommunicatively linked with the first data processing system via anetwork, wherein the second data processing system stores a secondcomponent of the Web application, and wherein the second componentcomprises at least a portion of the Web application not included in thefirst component; wherein the first data processing system is a firstserver system and the second data processing is a second server systemdifferent than the first server system.
 8. A computer program product,comprising: a computer readable storage medium having stored thereonprogram code that, when executed configures a processor to performexecutable operations comprising: generating a cache manifest for a Webapplication, wherein the cache manifest specifies a Web page of the Webapplication; determining a resource that is required by the Web page;building a closure collection including the resource required by the Webpage; writing a reference indicating the resource to the cache manifest;separating the Web application into a first component comprising theclosure collection and the cache manifest and a second component,distinct from the first component, including at least a portion of theWeb application not included in the first component; deploying the firstcomponent to a first server system; and deploying the second componentto a second server system different than the first server system.
 9. Thecomputer program product of claim 8, wherein determining a resource thatis required by the Web page comprises: determining a target specified bythe Web page as the resource.
 10. The computer program product of claim8, wherein the computer readable storage medium further stores computerreadable program code that, when executed, configures a processor toinitiate an executable operation comprising: determining that theresource is a static resource.
 11. The computer program product of claim8, wherein each resource included within the closure collection is astatic resource.
 12. The computer program product of claim 8, whereinthe computer readable storage medium further stores computer readableprogram code that, when executed, configures a processor to initiate anexecutable operation comprising: compressing at least a portion of theclosure collection.
 13. The computer program product of claim 8, whereinthe closure collection comprises at least a first resource and a secondresource, wherein the computer readable storage medium further storescomputer readable program code that, when executed, configures aprocessor to initiate an executable operation comprising: consolidatingthe first resource and the second resource into a single, consolidatedresource.